The invention relates to a two cycle internal combustion engine with uni-directional flow scavenging of a cylinder wherin the cylinder wall includes, in the area of the lower dead center location of the piston, inlet passages for the introduction of fresh gas into the combustion chamber defined by the cylinder wall and which is provided with an oil circuit for the lubrication of the piston in the cylinder.
Such a two cycle engine is known for example from U.S. Pat. No. 2,043,296.
However, the two cycle engine design described in this patent has the disadvantage that the piston top land, that is, the piston portion between the uppermost annular groove and the piston top becomes very hot during the operation of the two cycle engine so that the piston top land is subjected high strain and that, furthermore, the emissions of the two cycle engine are relatively high particularly because lubricating oil which is utilized for the lubrication of the piston within the cylinder enters the combustion chamber of the two cycle engine and is combusted therein.
It is the object of the present invention to provide a two cycle internal combustion engine with uni-directional flow scavenging without the disadvantages inherent in the arrangements of the prior art, particularly, an engine wherein the strain to which the piston top land is exposed is relatively small and also the emissions are low.